The Library Design and Analysis Core Laboratory (LDA laboratory, Core C) is responsible for assisting with the design of diverse libraries and carrying out the spectroscopic characterization of library members. The specific aims of the LDA core laboratory are as follows: Specific Aim 1. The LDA core laboratory will provide the research projects and Synthesis core laboratory with the computational facilities for managing chemical structures and data, for predicting key physicochemical properties of compounds to be synthesized, and for guiding the design of diverse libraries. Specific Aim 2. The LDA core laboratory will provide automated, high throughput mass spectrometry and NMR analysis to confirm the identity and purity of compounds in libraries.